Chapter 15, Problem 1E

Summary Introduction

Introduction:

The synthesis of new erythrocytes or red blood cells happens in the bone marrow and the process is known as erythropoiesis. The synthesis of new red blood cells is simulated by the decreased oxygen level in circulation which is detected by kidneys resulting in hormone erythropoietin. The hormone in turn causes the proliferation and differentiation of red blood cells.

Answer to Problem 1E

Solution:

The correct answer is option (d) Bone Marrow.

Explanation of Solution

Explanation/justification for the correct answer:

The correct option is (d), Bone Marrow.

Erythrocytes, being the major components of blood, carries oxygen and carbon dioxide to and from the cells and tissues. The erythrocytes, also termed as redblood cells or RBCs, have a protein called Hemoglobin that binds with oxygen molecules and helps in its transfer to different cells and tissues. As these cells don’t have nucleus, it is not formed by cell division. Due to its short life span, RBCs are formed on everyday basis.When the old RBCs are destroyed, the oxygen level in our body decreases and this triggers the kidney to secrete hormone erythropoietin into the bloodstream which travels to the bone marrow. In the bone marrow it differentiates the pluripotent cells and forms the erythrocytes.

Explanation for incorrect answer:

The option (a) is liver.

The liver is related to the breakdown of RBCs. The liver is responsible for converting the bilirubin into bile. Hence, this is an incorrect option.

The option (b) is spleen.

The dead and old RBCs are removed by the help of macrophages present in the Spleen. Hence, this is an incorrect option.

The option (c) iskidney.

The kidney is responsible for the production of erythropoiesis which stimulates the production of RBCs in the bone marrow. Hence, this is an incorrect option.

The option (e) is heart.

The heart is responsible for the pumping of oxygenated and the deoxygenated blood to the respective parts of the body. Hence, this is an incorrect option.

Conclusion

We can conclude that production of RBCs or Erythrocytes takes place in the bone marrow and this process is known as erythropoiesis.Therefore, correct option is (d) Bone Marrow.